Bellator president Scott Coker broke the news to MMAJunkie.com on Monday. Bader, 33, formally announced the signing on The MMA Hour. The news came less than a week after sources informed ESPN.com that Bader had obtained his official release from the UFC, his former employer.

Bader has won six of his past seven fights and is the No. 4-ranked light heavyweight in the world, according to ESPN.com. Per Haljestam-USA TODAY Sports

Coker seemed thrilled to add Bader to the Bellator group.

"It's not every day you are able to sign a top-10 athlete, let alone two in the same week," Coker said. "That's exactly what happened with Ryan Bader and [welterweight] Lorenz Larkin.

"As I've said regarding our free-agent policy, we want to bring guys into Bellator that make sense from multiple angles for both parties: the fighter and the promotion. Bader fits that mold. My phone has been ringing off the hook with guys that are chomping at the bit to get in the cage with Bader, and we hope to have some news regarding his debut soon."

An official debut date has not been scheduled, though Bader (22-5) could be in line for an immediate shot at Bellator's 205-pound championship. Bader holds a 2015 victory over Phil Davis, the division's current titleholder.

A former collegiate wrestler at Arizona State University, Bader broke into the UFC as the winner of The Ultimate Fighter reality series in 2008. He jumped to a 4-0 start inside the Octagon, which set up a high-profile matchup against then 23-year-old Jon Jones. Jones won that fight by second-round submission.

Bader has fought many of the biggest names of his division, including Jones, Tito Ortiz, Quinton 'Rampage' Jackson, Anthony Johnson and Rashad Evans, among others. He has won six of his past seven fights and is the No. 4-ranked light heavyweight in the world, according to ESPN.com.

He is coming off a TKO win over Antonio Rogerio Nogueira in November. It was well-known that Bader entered free agency following that win. Last month, UFC president Dana White stated that he intended to waive the promotion's matching right for Bader, but it did not become official until last week.